The invention relates to a member for stabilizing cervical vertebrae.
The German patent 39 23 995 discloses a stabilizing member for stabilizing cervical vertebrae. This member comprises a plate, which is bent to adapt it to the desired shape of the cervical spinal column. Thereafter, a plurality of bolts are screwed into the individual adjacent vertebrae. If the surgeon determines that the bending line is not perfect or must be changed for medical reasons, all screws must again be unscrewed in order to rebend the plate. This should be followed by again screwing in the bolts; For stability reasons of the vertebrae such a renewed screwing operation is hardly possible because of the weak anchoring in the bone so that in practice it must be done without such a later correcting alignment. The U.S. Pat. No. 5,312,404 discloses a member for stabilizing vertebrae which comprise a body with a plate-shaped portion and a bore extending perpendicular to the plane of the plate. A bone screw with a threaded portion and a head is provided, whereby the threaded portion extends through the bore towards a first side of the plane of the plate and the head of a bone screw is supported by the plate-shaped portion. The member has a second portion which is laterally offset with respect to the bore in the plane of the plate adjacent to the plate-shaped portion. The second portion comprises a bore for receiving a rod. A threaded bore for receiving a screw is provided perpendicular to the axis of this bore. The rod is fixed by means of a screw screwed into this threaded bore.
The U.S. Pat. No. 5,360,429 discloses a member for stabilizing vertebrae which consists of a body with a plate-shaped portion and a laterally offset second portion. The second portion comprises a slit which is provided with an external screw thread and serves for receiving a rod to be supported therein. A nut cooperating with the external screw thread serves for locking the rod to be placed therein.
It is the object of the invention to provide a member for stabilizing cervical vertebrae wherein the rod to be received is permanently locked.
This object is achieved by the member for stabilizing cervical vertebrae characterized in claim 1. Further developments of the invention are characterized in the subclaims.